Magnetic switch



March 20, 1934. E. G, JOHANSSON 1,951,362

MAGNETIC SWITCH Filed Feb. 26, 1950 220m??? imaZ'fiia/arm M 04W G -MWW Patented Mar. 20, 1934 UNITED STATES setts Application February 26, 1936, Seriai Ne. 681,526

4 (Claims.

This invention relates to magnetically controlled switch mechanism and has for an object to provide a double throw switch which may be op-= erated to break one circuit and make another circuit with a very rapid action and which will be held firmly in either of its contactmaling positions without the use of mechanical interlocks or latches. V

For a more complete understanding of this invention, reference may be had to the accompanying drawing in which Figure 1 is a plan View of a double pole switch constructed in accordance with this invention.

Figure 2 is a section on line 2--2 of Figure 1.

Figure 3 is a side elevation of the switch.

Figure 4 is a detail section on line i l of Figure 1.

Figure 5 is a diagrammatic view of a circuit for which the switch is particularly suitable.

Referring to the drawing at 1 is indicated a suitable supporting insulating base, which, as shown, is provided with four spaced contact terminals 2, 3, 4 and 5 upstanding therefrom, this particular embodiment showing a double pole double throw switch, although it will be evident from further description that any number of pairs of poles might be used as desired.

Cooperating with these terminals are the two switch arms 6 and 7. These switch arms are supported for rocking movement about an axis 8 so that the arm 6 may contact either with the terminal 2 or with the terminal 3, but not with both at the same time and the arm 7 may contact with either the terminal 4 or the terminal 5, but not with both at the same time. As shown in Figure 2 the axis 8 is defined by a pair of pivots in alinement with each other, these pivots securing a pair of arms 9 and 10 to suitable supporting uprights 11 and 12. These uprights as shown are formed of conducting material and have at their lower ends out-turned terminal portions 13 and 14 which are in electrical connection through the pivots 8 with the switch arms 6 and 7, respectively. The arms 9 and 10 are formed angular, having upper flat portions 15 and 16 extending toward each other and fixed to suitable insulation strips 17 and 18. These insulation strips 17 and 18 are bridged at opposite ends by armature members 19 and 20 secured'thereto by screws 70 and which are positioned in line with the cores 21 and 22 ofpairs of electromagnets 23 and 24. It is evident, therefore, that when the electromagnets 23 are energized the magnets 24 being deenergized, the armature 20 will be drawn to the cores 21, rocking the members 15 and 16 so as to bring the switch arm 6 into engagement with the contact 3, and the switch arms 7 into engage= ment with the contact 5, while if the electromag nets 24 are energized and the electromagnets 23 are de-energized, the switch arm 6 will be brought into engagement with the contact 2 and the switch arm 7 into engagement with the contact 1-. The protruding ends of the screws 70 may act as stops to engage the core ends to prevent actual contact of the armature and the cores.

When the switch arms 6 and 7 are in engagement with the contacts 3 and 5, respectively, the armature 20 being close to or in engagement with the cores 21, energization of the magnets 24 will not be able to change the positions of the switch arms 6 and 7, since in that position of the parts the armature 19 is spaced from the pole pieces 22 so that the magnets 24- are less effective to draw the armature 19 than are the magnets 23 to hold the armature 20, which is close to the cores 21, so that the switch arms 6 and 7 are retained in their positions engaging the contacts 3 and 5. Likewise when the armature 19 is close to the pole pieces 22 so that the switch arms 6 and 7 are in engagement with the contacts 2 and 4, energization of the electromagnets 23 will not be able to change the positions of the switch arms 6 and 7.

As shown in Figure 5 the electromagnets 23 and 24 are arranged in series in a circuit deriving potential from the line wires 50 and 51, suitable terminals 52 and 53 being shown in Figure 1 for these connections. There is also a connection intermediate the two sets of coils 23 and 24 at the point 55 which leads to a supplemental switch 56 shown in Figure 5. This switch may be brought into contact with either of a pair of terminals 57 or 58. When this switch is in contact with the terminal 58, as shown in Figure 5 in full lines, it acts to short circuit the coils 22, while when the switch 56 is in contact with the terminal 5'7, it acts to short circuit the coils 24. The terminals 3 and 5 are shown connected to opposite poles of a source of potential at 60 and the terminals 2 and 4 are shown as connected to opposite poles of another source of potential 61, while the terminals 13 and 14 of the switch arms are shown as connected to a suitable load circuit, the load being indicated at 65. The two sides of this load circuit are preferably connected through a condenser 66. If now the Wit switch 56 be placed in engagement with the contact 56, as shown in Figure 5, thus short circuiting the coils 23, the coils 24 are energized and draw and hold the switch arms 6 and 7 to make contact with the terminals 2 and 4, thus to connect the source of potential 61 to supply the load circuit. If this switch 56 is then moved toward the contact 57 suiliciently to break contact at 58, both sets of coils 23 and 24. are energized, but as the coils 23 arev in relatively inefficient magnetic coupling with their armature 20, the positions of the switch arms 6 and '7 remain undisturbed. As soon, however, as contact is made by the switch 56 with the terminal 57, the coils 24. are de-energized while the coils 23 remain energized. Thus the holding power for the switch arms 6 and '7 to make contact with the source of potential 61 is broken and the switch arms 6 and 7 are immediately moved to break contact with the terminals 2 and 4 and to make contact with the terminals 3 and 5. Thus the source of potential 61 is cut out from supplying the load circuit while the source of potential 60 is immediately cut in to supply this circuit. This action is so quick that in the interval when neither source of potential 60 or 61 is in the circuit, the load may be fed from the condenser 66 so that no apparent disconnection of the source of potential from the load will occur, provided the condenser 66 is of sufficiently large capacity. It is however commercially practicable to employ such a condenser of reasonable dimensions. While this switch mechanism is particularly suitable for the function illustrated in Figure 5, it should, of course, be understood that it is not limited to this, but might be employed wherever it is desired to effect a quick make and break and without the employment of mechanical devices for maintaining the switch in either of its two positions. Likewise it is apparent that while a double pole switch has been shown any number of 'poles desired might be employed.

Having thus described an embodiment of this invention, it should be evident that various modifications and changes might be made therein Without departing from thespirit or scope of the invention as defined by the appended claims.

I claim:

1. A mechanism of the class described comprising a pair of terminals, a switch arm movable into contact with either of said terminals and out of contact with the other of said terminals, a pair of electromagnetic means each tending when energized to move said arm to and hold said arm in one of its contacting positions, the moving and holding force exerted on said arm being strongest when said arm is in the contacting position to which it is drawn thereby, said electromagnetic means being arranged in series, and means for selectively short circuiting either of said electromagnetic means whereby the other of said means may draw and retain said arm. into its contact position until such one means has been energized and the other means has been short circuited.

2. A mechanism of the class described comprising an insulating base, a pair of spaced conducting uprights, conducting arms pivoted to said uprights in axial alinement with each other, said arms having end portions extended toward each other, switch arms centrally carried by the opposite end portions of said conducting arms, a pair of contacts for each switch arm with either of which said switch arm may engage when swung away from-the other, blocks of insulation fixed to the adjacent ends of said pivoted arms, spaced armatures fixed to opposite ends of said blocks and securing said pivoted arms together for simultaneous rocking about their respective pivots, an electromagnet positioned adjacent to each armature, means for selectively energizing said electromagnets to swing said switch arms into engagement each with a corresponding one of its contacts, and means for connecting conductors to said uprights.

3. A mechanism of the class described comprising a pair of switch points, a switch arm pivotally mounted to rock into contact with ,one or the other of said points, a pair of electromagnets each having a core, said electromagnets being connected in series with a source of electric energy, an armature mounted to rock with said arm, said armature having spaced portions respectively adjacent to said cores and movable alternately toward and from their respective cores, the armature portion nearest its core being attracted more strongly than the other when the electromagnets are equally energized, and means for selectively short-circuiting either electromagnet.

4. A mechanism of the class described, comprising a pair of electromagnets with fixed cores, armatures for said magnets, means connecting said armatures for simultaneous opposite movements toward or from the cores of their respective magnets whereby movement of either armature into proximity to the core of its magnet is accompanied by movement of the other armature out of proximity to the core of its magnet, means normally connecting said magnets in series with a source of electric energy, and means for selectively short-circuiting either or neither of said magnets.

ERNEST G. JOHANSSON, 

